Consider the following statements :

While diluting concentrated nitric acid solution

$1.$ The concentration of $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$ ions/ volume increases

$2.$ Water must be added slowly to concentrated acid.

$3.$ Acid must be added slowly to water.

Which of the statements given above is/are correct?

Which of the following statements is/are correct?

$1$. All the bases are alkali.

$2$. All alkalis dissolve in water.

$3$. Alkalis are soapy to touch, bitter in taste and corrosive in nature.

Select the correct answer using the code given below :

Match List I with List II and select the correct answer using the code given below the lists:

List I                                                                      List II

(Use)                                                               (Compound)
A. Boric acid                                                    $1.$ Antiseptic
B. Citric acid                                                     $2.$ Food preservative
C. Magnesium hydroxide                                $3.$ Antacid
D. Acetic acid                                                  $4.$ Pickle

In the reaction $\mathrm{B}(\mathrm{OH}{)}_3+2{\mathrm{H}}_2\mathrm{O}⟶{\left[\mathrm{B}(\mathrm{OH}{)}_4\right]}^{-}+{\mathrm{H}}_3\mathrm{O}$

$\mathrm{B}(\mathrm{OH}{)}_3$ functions as